At this point it just refers to ‘next generations after 2nm’. Not only does the process obviously not exist, they haven’t decided on what transistor structure to use either whether GAAFET or a successor.

It means density of transistors per square mm in relation to TSMC N3 (‘3nm’) and N2 (‘2nm’

Rapidus was created last year and only started clearing the plot of land to build their first fab in September. Talking about 1nm production is putting the cart before the horse, they aren’t expecting their first 2nm node to be in production until 2027.

They talk about production only insofar that production will be possible when they have developed the required technology.
Developing technology that enables production of the next smaller node takes increasingly more time, so starting to develop that technology now is appropriate if you want a chance of having it 10 to 15 years down the road.

I was at GloFlo when it happened. They shut down because of lack of customers and Mubadala did not want to fund another process tech which was not going to bring any profits.

But your point is still valid, even if they did somehow come up with a process recipe, with HVM worthy defect density, meeting their perf targets, they have to get customers. All this will easily take a decade.